To report an outbreak of respiratory synctyial virus (RSV) in a long-term care facility (LTCF) during ongoing routine respiratory illness surveillance.Rapid antigen testing, viral culture, direct fluorescent antibody (DFA) testing, and reverse transcriptase polymerase chain reaction (RT-PCR) testing for up to 15 viruses in symptomatic residents and chart review.A 120-bed LTCF.Comparison of rapid antigen testing, respiratory viral cultures, and DFA testing and RT-PCR in residents with symptoms of a respiratory tract infection.Twenty-two of 52 residents developed symptoms of a respiratory tract infection between January 29, 2008, and February 26, 2008. RSV was detected using RT-PCR in seven (32%) of the 22 cases. None of the seven cases had positive RSV rapid antigen testing, and only two had positive culture or DFA results. This outbreak occurred during a time when state wide RSV rates were rapidly declining. One patient was admitted to the hospital during the infection and subsequently died.RSV may cause outbreaks in LTCFs that traditional diagnostic methods do not detect. RT-PCR can provide a more timely and accurate diagnosis of outbreaks, which allows for early symptomatic treatment, rational use of antibiotics, and improved infection control.